<template>
    <div>
      <!-- 评论列表 -->
      <div class="cmt-list" :class="{'art-cmt-container-1':isShowCmtBox,'art-cmt-container-2':!isShowCmtBox}">
        <!-- 评论的 Item 项 -->
        <van-list
          v-model="loading"
          :finished="finished"
          finished-text="没有更多评论了，请发表评论"
          @load="onLoad"
          :immediate-check="false"
        >
          <div class="cmt-item" v-for="obj in commentArr" :key="obj.com_id">
            <!-- 头部区域 -->
            <div class="cmt-header">
              <!-- 头部左侧 -->
              <div class="cmt-header-left">
                <img :src="obj.aut_photo" alt="" class="avatar">
                <span class="uname">{{obj.aut_name}}</span>
              </div>
              <!-- 头部右侧 -->
              <div class="cmt-header-right">
                <van-icon name="like" size="16" color="red"
                v-if="obj.is_liking === true" @click="likeFn(true,obj)"/>
                <van-icon name="like-o" size="16" color="gray" v-else
                @click="likeFn(false,obj)"/>
              </div>
            </div>
            <!-- 主体区域 -->
            <div class="cmt-body">
              {{ obj.content }}
            </div>
            <!-- 尾部区域 -->
            <div class="cmt-footer">{{ timeAgo(obj.pubdate) }}</div>
          </div>
        </van-list>
      </div>
      <!-- 发表评论容器 -->
       <div>
        <!-- 底部添加评论区域 - 1 -->
          <div class="add-cmt-box van-hairline--top" v-if="isShowCmtBox === true">
              <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
              <div class="ipt-cmt-div" @click="toggleShowFn">发表评论</div>
              <div class="icon-box">
                  <van-badge :content="totalCount === 0?'':totalCount" max="99">
                      <van-icon name="comment-o" size="0.53333334rem" @click="commentClickFn"/>
                  </van-badge>
                  <van-icon name="star-o" size="0.53333334rem" />
                  <van-icon name="share-o" size="0.53333334rem" />
              </div>
          </div>

          <!-- 底部添加评论区域 - 2 -->
          <div class="cmt-box van-hairline--top" v-else>
              <textarea placeholder="友善评论、理性发言、阳光心灵"
              v-fofo @blur="blurFn" v-model.trim="comText"></textarea>
              <van-button type="default" :disabled="comText.length === 0" @click="sendFn">发布</van-button>
          </div>
       </div>
    </div>
  </template>

<script>
import {
  commentsListAPI, commentLikingAPI, commentDisLikingAPI
  , commentSendAPI
} from '@/api'
import { timeAgo } from '@/utils/date'
export default {
  data () {
    return {
      offset: null, // 偏移量评论ID
      commentArr: [], // 评论列表
      isShowCmtBox: true, // 底部显示短/高的评论容器
      totalCount: '', // 评论总数量
      comText: '', // 发布评论的内容
      loading: false,
      finished: false,
      lastId: null
    }
  },
  async created () {
    const res = await commentsListAPI({
      id: this.$route.query.art_id
    })
    console.log(res)
    this.commentArr = res.data.data.results
    this.totalCount = res.data.data.total_count || ''
    this.lastId = res.data.data.last_id
    if (res.data.data.results.length === 0) { this.finished = true }
  },
  methods: {
    timeAgo,
    // 评论
    async likeFn (bool, commentObj) {
      if (bool === true) {
        // 用户点在红心
        commentObj.is_liking = false
        await commentDisLikingAPI({ comId: commentObj.com_id })
      } else { // 用户点在灰心
        commentObj.is_liking = true
        await commentLikingAPI({ comId: commentObj.com_id })
      }
    },
    // 显示 - 评论输入框（第2套-高)
    toggleShowFn () {
      this.isShowCmtBox = false
    },
    // 评论按钮 - 点击事件 - 把第一条评论滑动到最上面
    commentClickFn () {
      // const articleHeight = document.querySelector('.article-container').scrollHeight
      // // console.log(articleHeight)
      // // window.scrollTo() 使网页进行滚动，设置相应的坐标，就可以让网页滚动到最顶端
      // // 如果底下没有内容了，则不再滚动
      // window.scrollTo(0, articleHeight)
      document.querySelector('.like-box').scrollIntoView({
        behavior: 'smooth'
      })
    },
    // 发布按钮 - 点击事件
    async sendFn () {
      // console.log(this.comText)
      const res = await commentSendAPI({
        id: this.$route.query.art_id,
        content: this.comText
      })
      this.commentArr.unshift(res.data.data.new_obj)
      this.totalCount++
      this.comText = ''
      this.commentClickFn()
    },
    blurFn () {
      setTimeout(() => {
        this.isShowCmtBox = true
      }, 0)
    },
    // 底部加载更多
    async onLoad () {
      if (this.commentArr.length > 0) {
      // 请求下一页数据
        const res = await commentsListAPI({
          id: this.$route.query.art_id,
          offset: this.lastId
        })
        this.commentArr = [...this.commentArr, ...res.data.data.results]
        this.totalCount = res.data.data.total_count || ''
        this.lastId = res.data.data.last_id
        if (res.data.data.last_id === null) { this.finished = true }
        this.loading = false
      } else {
        this.loading = false
      }
    }
  }
}
</script>

  <style scoped lang="less">
  .cmt-list {
    padding: 10px;
    .cmt-item {
      padding: 15px 0;
      + .cmt-item {
        border-top: 1px solid #f8f8f8;
      }
      .cmt-header {
        display: flex;
        align-items: center;
        justify-content: space-between;
        .cmt-header-left {
          display: flex;
          align-items: center;
          .avatar {
            width: 40px;
            height: 40px;
            background-color: #f8f8f8;
            border-radius: 50%;
            margin-right: 15px;
          }
          .uname {
            font-size: 12px;
          }
        }
      }
      .cmt-body {
        font-size: 14px;
        line-height: 28px;
        text-indent: 2em;
        margin-top: 6px;
        word-break: break-all;
      }
      .cmt-footer {
        font-size: 12px;
        color: gray;
        margin-top: 10px;
      }
    }
  }
  /*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}

// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}

.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}

// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
  </style>
